Down lighting systems and fixtures thereof

ABSTRACT

A down lighting system for elevator cabs and the like includes halogen lights in standard and emergency light fixtures. Both types of fixtures are connected to the ceiling by a clamp arrangement which is universally adaptable to a wide variety of ceiling types without changing the light housing dimensions. The clamp arrangement fastens light housings against rotation with respect to the ceiling and it is adjustable to different height ceiling configurations merely by connection to different vertical positions of the outer surface of the fixture. The standard fixture includes a halogen bulb with its own reflector. The emergency lighting fixture includes a halogen bulb/reflector unit with the emergency self focusing bulbs concentrically spaced around it. Both light sources pass focused light directly into the space below the ceiling for meeting test point candle power requirements. The emergency lighting circuit includes a switching relay with a manually operated button for testing the emergency light source by pulling the button to override a relay armature.

This is a continuation-in-part application of U.S. Ser. No. 07/672,415filed Mar. 20, 1991, now U.S. Pat. No. 5,145,247, which is acontinuation-in-part of Ser. No. 448,222, filed Dec. 11, 1989, now U.S.Pat. No. 5,003,432, issued Mar. 26, 1991, which is a continuation ofSer. No. 191,423, filed May 9, 1988, now U.S. Pat. No. 4,890,200.

BACKGROUND OF THE INVENTION

This invention relates to lighting systems and more particularly to downlighting systems including down lighting emergency lights for elevatorcabs and other spaces requiring high efficiency main lighting as well asintegrated emergency lighting operative on failure of a main lightingpower supply.

Lighting systems for various overhead ceiling systems require that lightunits be connected to a power supply through various wiring networks andconnection arrangements.

It is known to provide standard 110 volt residential or commercialfixtures in overhead ceilings. In some cases the bulbs are 12 volt bulbsenergized from a 110 volt system via individual step down transformersconnected to power the 12 volt bulbs.

It is also known to provide a plurality of 110 volt bulbs connected to a110 volt wiring system. The bulbs are mounted either above a egg-cratetype grill covering or are hidden by a cover which will diffuse lightfrom the bulbs. In some cases these systems are lighted by means offluorescent tube lighting.

In cases where 12 volt bulbs are used, a large numbers of fixtures andbulbs are needed to provide enough candle power to illuminate the spacebelow the ceiling system.

Existing down lighting systems use low light output bulbs which haveshort life or are operated at lower than design voltage to extend thebulb life, but all of which requires a large number of fixtures andelaborate wiring systems for connecting the fixtures to a power source.

In the case of elevator down lighting systems, it is desirable toprovide as much direct lighting as possible from the main illuminatinglamps both to reduce the number of fixtures required for a given area ofceiling and to reduce the complexity of the wiring system for supplyingpower to the individual fixtures.

A further problem with known elevator down light systems is that theemergency light source for the elevator is either located in thevicinity of the elevator control panel or is located at an overheadlocation above the ceiling. Such arrangements require a separate fixturefor the emergency lighting. Also, in some cases the emergency light ishidden and it may be necessary to "bend" the light to produce a desired"test point" illumination within the elevator cab. Such emergency lightsrequire more wattage which, in turn, require a larger, more expensivebattery and attendant charger.

Another known emergency light system uses two of the down lightsnormally used for cab illumination. This system is expensive because itrequires a large battery pack and charger for each light. Further, oneor both bulbs may be burned out when called upon for the emergency mode.

SUMMARY OF THE INVENTION

Accordingly, an object of my invention is to provide a one piece, lowprofile, down lighting fixture which will provide direct focusedlighting within the space below an overhead ceiling and wherein the lampfixture is readily mounted to the ceiling by a wiring system whichreadily fits within low clearance plenums.

Another object of my invention is to provide such a down lighting lampfixture and a fastener system which universally adapts the fixturehousing for mounting on a variety of different height and clearanceceiling configurations.

A feature of the present invention is to provide such a lamp fixturewherein the housing includes a flanged open end and a closed end. Theflanged open end is adapted to cover a fixture access hole through theceiling and it has a diameter in excess of that of said housing topermit insertion of the housing through the access hole while defining aretention surface engageable with the outer surface of the ceiling so asto provide a locking engagement between the housing at the outer surfaceof the ceiling.

Another feature is to provide a fixture of the type set forth in thepreceding paragraph and to further provide a retainer member extendingvertically from the inner surface of the ceiling immediately adjacentthe ceiling access hole and in close spaced parallelism with the outersurface of the housing. A retainer clamp surrounds the outer surface ofthe housing when it is inserted through the access opening and includingmeans operative to force the retainer member into locking engagementwith the outer surface of the housing while directing a hoop force onthe housing which is radially opposed to the force of the retainermember and wherein the hoop retention force can be imposed on thehousing anywhere along its height to accommodate for different thicknessceilings.

Still another feature is to reduce the "wired" profile of such fixturesby including a low profile conduit fitting that connects wires from aflexible conduit to socket means located inboard of the housing fixture.

Another object of my invention is to provide a ceiling mount fixture formounting an illuminating bulb on different thickness ceilings and forconnection to a flexible conduit type wire system by means of a fixturehousing which is universally adaptable to different thicknesses ofceiling by use of a housing including an open end and a closed end. Theopen end has a diameter in excess of that of the housing to permitinsertion of the housing through the access hole while defining aretention surface engageable with the outer surface of the ceiling whenthe fixture is mounted on the ceiling and a vertically oriented surfaceadaptable to be engaged by hoop type connectors immediately inboard ofthe inner surface of the ceiling so as to allow mounting of the fixturein low clearance plenums.

Yet another object of my invention is to provide a fixture for mountingon a ceiling in which first socket means are connected inboard of thehousing for receiving a main source of illumination for directingregular illumination to a space below said ceiling; and wherein secondsocket means are connected inboard of the housing and concentric withthe first socket means and adapted to be connected to an emergency powersource for directing emergency lighting from the open end of saidhousing so as to provide an emergency source of illumination in thespace below said ceiling upon primary or main power failure.

Another feature of my invention is to provide the fixture of thepreceding object wherein the first socket includes a halogen bulb, alight reflector surrounding said bulb to direct the light from saidhalogen bulb vertically downwardly through said housing and a safetyglass cover to diffuse light from the halogen bulb while serving toprevent shards from a broken halogen bulb from escaping through the openend of the fixture.

Yet another feature of my invention is to provide such a halogen bulbmounted in the center of the fixture and to provide secondary socketslocated concentrically around the halogen bulbs to receive dedicatedself focusing bulbs selectively connected to an emergency power pack fordirecting light downwardly through space in the housing for lighting thespace below the ceiling light fixture upon a main power supply failure.

Another feature of the invention is to provide a housing of the type setforth above wherein the light source is in the form of a single endedfluorescent bulb having a free end located closely adjacent the open endof the fixture to provide down lighting therefrom and an opposite endcarried by a base connected to a socket on the closed end of thefixture.

In one embodiment, a light system provides emergency lighting andregular illumination. One of the regular lights and the emergency lightsshare a common fixture with said housing including an open end and aclosed end. The open end has a diameter in excess of that of saidhousing to permit insertion of the housing through the access hole whiledefining a retention surface engageable with the outer surface of theceiling when the fixture is mounted on the ceiling.

First socket means are connected inboard of the housing for providing afirst primary source of illumination for directing regular illuminationto a space below said ceiling.

Second socket means are connected inboard of the housing and concentricwith said first socket means and are adapted to be connected to anemergency power source for directing emergency lighting from the openend of said housing so as to provide an emergency source of illuminationin the space below said ceiling during periods when the primary light isinoperative because of power failure. While such secondary socket meansare shown as concentric, other offset locations are contemplated withinthe scope of my invention.

The one embodiment includes emergency lighting circuit means forconnecting the second socket means to a source of emergency power whenthe power supply for the first primary source of illumination fails.

The emergency lighting circuit means includes a battery defining arechargeable d.c. power source for emergency power, a battery chargerhaving input terminals connected to the primary power source and outletterminals for supplying charging current to the battery.

A double pole, double throw relay has a first pair of contacts and asecond pair of contacts. A solenoid controlled armature is operativelyconnected to the first and second pairs of contacts. It is energized bythe primary power source and positions the first pair of contacts tosupply charging current to said battery as long as the primary powersource is on. When the primary source of power fails, the solenoidpositions the second pair of contacts to connect the battery to thesecond socket means so as to energize lamp means therein to provideemergency lighting.

A manually operative test button on the armature provides the means formanually disconnecting the first pair of contacts and connecting thesecond pair of contacts to connect the emergency lamp means to thebattery to test emergency lighting when the primary power source isoperative.

The previous embodiments of the invention can include three (3)emergency bulbs having focusing lens on the ends of the bulbs to providea low level of illumination, viz. 0.2 foot candles minimum, underemergency lighting conditions. The light level is selected to enable anoccupant of the elevator to locate and operate the push alarm buttonand/or the emergency cab phone located in the elevator in order to callfor help.

Another feature of the present invention is to supplement such emergencybulbs with a long life, low current device for illumination, e.g. alight emitting diode or L.E.D. and locating the L.E.D. behind or in atranslucent "alarm" button. Thus, under conditions in which the mainpower fails a battery power source is connected to both the emergencybulbs and the L.E.D. to illuminate the alarm button so that there is nomistaking its location. To attract even more attention the low currentdevice can be of the flashing or blinking type.

Another feature of the invention is to provide such a light source onthe emergency cab telephone cover behind or in an indicator buttonlocated on or in the vicinity of the telephone cover. In cases where theemergency phone is replaced by a speaker phone the illumination sourcecan be located in the button which is operated to automatically dial thephone or push it to directly talk without dialing.

Still another feature of the invention is to provide an improved systemfor locating and illuminating a phone box in an elevator to locate itwhen the main power system fails. The system is simpler and lessexpensive than speaker phone systems which are often used in place ofstandard cab phones located in an elevator since in the past standardcab phones have been vandalized or stolen. The improved system of thisinvention enables a standard cab phone to be located in the cab behind aselectively opened access door. The improved system includes a solenoidoperated latch which is normally maintained locked when the main poweris functioning. Under emergency conditions the locking latch isenergized by the emergency D.C. power source to release the access doorso as to expose the phone and wherein the improved system furtherincludes an emergency light within the phone compartment thatilluminates when the emergency power source is connected to draw anoccupant's attention to the phone. If desired the emergency light can beof the flashing variety to provide still further attention.

Still another feature of the present invention is to provide theimproved elevator cab phone lighting system of the preceding paragraphwherein the light source within the phone box is provided by locating aplurality of emergency lights in either the box or on the access door soas to concurrently aid in identifying and locating the emergency phonewhile providing a low level illumination of the elevator cab underemergency conditions.

Other objects, features and advantages of the present invention will bereadily appreciated as they become better understood with reference tothe following description when considered in conjunction with theaccompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an elevator cab including anoverhead lighting system in accordance with the present invention;

FIG. 2 is an enlarged sectional view taken along the line 2--2 of FIG. 1looking in the direction of the arrows;

FIG. 3 is a vertical sectional view taken along the line 3--3 of FIG. 2looking in the direction of the arrows with the light bulb socketremoved;

FIG. 4 is a fragmentary sectional view taken along the line 4--4 of FIG.2 looking in the direction of the arrows;

FIG. 5 is a diagrammatic view of an emergency lighting fixture inaccordance with the present invention;

FIG. 6 is a sectional view of an emergency bulb and socket assemblytaken along the line 6--6 of FIG. 5;

FIG. 7 is another embodiment of the light fixture of the presentinvention;

FIG. 8 is a diagrammatic view of an emergency lighting circuit andcontroller in accordance with my invention;

FIG. 8A is a diagrammatic view of a relay coil;

FIG. 9 is a schematic view of an emergency lighting circuit includinganother embodiment of the invention;

FIG. 10 is a diagrammatic view of still another embodiment of theinvention;

FIG. 11 is an enlarged sectional view taken along the line 10--10 ofFIG. 11;

FIG. 12 is an enlarged sectional view like FIG. 11 showing an accessdoor in its open position;

FIG. 13 is an enlarged sectional view like FIG. 11 showing anotherembodiment of the invention;

FIG. 14 is a view like FIG. 13 showing an access door in its openposition;

FIG. 15 is a sectional view of another light fixture embodiment;

FIG. 16 is a top elevational view of FIG. 15; and

FIG. 17 is a sectional view of another light fixture embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIG. 1, the down lighting system 10 of the presentinvention is shown in association with a ceiling 12 in an elevator cab14 which has two walls thereof broken away for clarity.

The elevator cab 14 has a control panel 16 and floor indicator lights 18of a known kind, as well as a pair of sliding doors 20. The interiorspace 22 of the elevator cab 14 is illuminated by a plurality of main(sometimes called a primary source of illumination) light fixtures 24one of which 26 provides main and emergency lighting (sometimes called asecondary source of illumination).

As shown in FIG. 2, each of the main light fixtures 24 (and 26) aresupported on the ceiling 12 at access holes 28 therein.

More particularly, each of the main light fixtures 24 (and 26) includesa housing 30 having a closed end 32 and a flanged open end 34 joinedrespectively to an intermediate tubular portion 35.

The flanged open end 34 has an outer diameter 36a which overlies theaccess hole 28 and which further defines a retention surface 36 thatengages the outer surface 38 of the ceiling 12 to lock the housing 30against further inboard movement with respect to the ceiling 12.

In accordance with certain principles of my invention, the housing 30 isheld in place on the ceiling 12 by a retainer assembly 40 of a form thatcan be adjustably positioned along its vertical surface 42 so as toenable the housing 30 to be universally adapted for mounting on a numberof different ceiling thicknesses as will be discussed. The retainerassembly 40 more particularly includes a single L shaped retainer 44with a lower leg that is connected to the inner surface 46 of ceiling 12by a single fastener 48, representatively shown as a screw element. Theupper leg of the L shaped retainer 44 is in close proximity to theaccess hole 28 and extends vertically upwardly of the surface 42.Consequently, it is positioned to engage a diametric point 52 on theouter surface 42 of the housing 30 as shown in FIG. 4.

The retainer assembly 40 also includes an annular clamp 50 which wrapsaround the full circumference of the outer surface 42 and against theoutboard surface 52 of the upper leg of the L shaped retainer 44. Itincludes a tensioning nut 53 which is positioned to be drawn outwardlyby a screw element 54 so as to draw end segments 56, 58 of the annularclamp together. As the clamp is tightened, the inboard surface 60 of theupper leg 44 is forced against the outer surface 42. Simultaneously, theclamp 50 applies hoop pressure between the inner surface 62 of theannular clamp 50 and the diametrically opposite surface segment 64 ofthe outer surface 42 of the housing 30 as shown in FIG. 4. Retainerassembly 40 is thereby readily adjustable along different points on theheight of the outer surface 42 of the housing 30 so as to be adjustableto different height or thickness ceilings 12. Consequently, the housing30 is a universal housing suitable for a wide range of different ceilingapplications. Furthermore, the arrangement enables such a universalhousing configuration to be firmly clamped between the retention surface36 and the retainer assembly 40 so that the assembled main light fixture24 will not rotate with respect to the ceiling 12 during bulbreplacement and following connection of a wiring system thereto suchthat the finally assembled fixture and bulbs mounted thereon willwithstand dynamic test conditions for elevator operation without damageor dislodgement from the ceiling 12.

The arrangement enables individual fixtures to be quickly assembled andplaced on the ceiling 12. Furthermore, the retainer assembly 40 is oflow cost while providing a desired structural integrity between the mainlight fixture 24 and the ceiling 12.

A further feature of the main lamp fixture 24 is that it can be locatedin low clearance plenum spaces such as illustrated by reference numeral66 in FIG. 1. More particularly, the housing 30 is configured so thatonly a reduced plenum height clearance is required to accommodate a highefficiency lamp source such as the halogen lamp assembly 70 of fixture24. The halogen lamp assembly 70 is shown mounted in a socket 72connected to the closed end 32 of the main light fixture 24.

More particularly, the conduit fitting 80 has a threaded end 74 thereonwhich is threadably received in an internally threaded bore 76 throughthe closed end 32. The threaded end 74 is locked to the outer surface ofthe closed end by a lock nut 78. The conduit fitting 80 has the oppositeend thereof secured by a clamp assembly 82 to one end of a flexibleconduit 84. The conduit 84 has wires 86, 88 directed therethrough tosupply 12 volt power to the power contacts on the socket 72. Thus, theflexible conduit 84 is connected to the lamp housing 30 so that wiringthereto will not be separated or dislodged during elevator operation orreplacement of bulbs in the fixture 24. In areas where electrical codedoes not require wire protection, the conduit 84 and conduit fitting 80may be deleted. Further, the socket 72 may be mounted as shown in FIG. 2or mounted on the top surface of closed end 32.

The socket 72 has a double contact bayonet connector into which the base90 of the halogen lamp assembly 70 can be inserted and rotated to locatethe retention pins 92 thereof in place and complete the electricalcontact of the filament 94 of a halogen bulb 96 to the wires 86, 88. Thehalogen lamp assembly 70 further includes a reflector 98 that will focusthe light from the filament 94 in a downward direction through the openend of the housing 30. The reflector 98 includes a bright inner surface100 and has a spun over end 102 that captures a protective lens 104which is secured on the end of the reflector 98 to keep the innersurface 100 clean. The lens 104 also prevents broken bulb fragments fromfalling into the elevator to meet protection requirements for downlighting systems of the type used in elevators.

The housing 30 has a plurality of air cooling holes 106 formed in theclosed end 32 as shown in FIG. 3. The closed end also includes holes 108to receive screws 110 for holding the mounting flange 112 of the socket72 in place on the closed end 32.

In a preferred embodiment, the housing 30 can be a single piece castingto define a strong base for the fixture 24. The flanged open end 34 canbe machined on the retention surface 36 and on the circumferentialsurface 36a and outer surface 36b for a finished appearance. The insidesurface 114 of the housing 30 can be machined smooth to provide apolished appearance or, alternatively, as illustrated, it can bethreaded through a segment 116 thereof to provide light rings for adiffused appearance when looking up into the cavity of the housing 30.

The closed end 32, in the illustrated arrangement, has six ventilatingholes 106, which are provided to keep the bulb temperature withindesired operating levels. In the illustrated arrangement, holes areconfigured to provide suitable ventilation for a 20 watt halogen bulb96.

The closed end 32 has a large central hole 76 machined therein for thebulb socket 72. The socket bracket 112 can be either screwed or rivetedin place. The resultant structure provides a strong, movement resistantbase into which bulbs can be changed without popping out the socket. Theinside diameter of housing 30 is large enough to provide for easyreplacement of the halogen lamp assembly 70 into and out of the closedend 32. Furthermore, the wires for the main light fixture 24 exit outthe end wall 32 for connection to a suitable power supply.

The central hole 76 can be threaded if flexible conduit is desired tocooperate with the lock nut 78 to securely fasten the conduit fitting 80in place to further provide a strong base which will not vibrate looseduring elevator operation and which will enable bulbs to be connectedand disconnected without affecting the wire connection to the socket 72.

A further aspect of the present invention is illustrated in FIG. 5,which shows a combined fixture 26 for main and emergency lighting. Thecombined fixture 26 is essentially the same as the lamp fixture 24 inFIG. 2 but with the addition of an emergency bulb and socket assembly120 formed in a side space 122 around a halogen lamp assembly 124.

A combined fixture 26 is mountable in ceiling 12 through access opening28 therein in the same manner as discussed with reference to thelighting unit 24. In the illustrated arrangement, the only difference isthe addition of two (or more) dedicated emergency light bulbs 126, 128,130 which have sockets 132 fixed to a mounting plate 135. The mountingplate 135 is fixed to the outer surface 134 of the closed end of thefixture by means of two screws 110 that are used for holding themounting flange 112 of the socket 72 for the halogen bulb. The emergencybulbs 126, 128, 130 are thus located in two of the vent holes 106 andallows the lens end 138 of bulbs 128, 130 to direct light energydownwardly through the open end 140 of the fixture 26. FIG. 6 shows themounting plate 135 with three sockets 132 and an opening 142 for thesocket 72.

FIG. 7 shows another embodiment of the invention in which the fixturehousing remains the same but has a side conduit fitting 141. In thisembodiment, the primary light source is a single ended fluorescent bulb143 having its base 145 connected to a socket 147 in the closed end of afixture housing corresponding to those previously discussed. The bulb143 is shown as a dual unit (quad units could also be used) which hastwo ends 143a, 143b for directing down lighting through the open end ofthe fixture. An advantage of the embodiment is provided by a reducedlateral dimension which results in more space for an emergency bulb andsocket assembly of the type shown at 120 in FIG. 5.

FIG. 7 illustrates an alternative mounting arrangement which locates ahousing 190 on the inner surface 192 of a ceiling 194. The housing 190is stabilized by two diametrically spaced L-brackets 196, 198 which areclamped to the housing 190 by a clamp 200 of the same configuration asclamp 50 in the FIG. 2 embodiment. Another feature of this mountingconfiguration is that it enables a trim bezel 202 to be inserted in theopen end of housing 190 to provide a thin, finished exterior appearance.The trim bezel 202 has a small diameter tubular extension 204 held inplace in the interior of the housing 190 by a plurality of spaced springclips 206. This arrangement reduces the light aperture for aestheticreasons and provides a flange 207 for covering the ceiling hole. It alsoenables the bezel to be removed for replacing the bulb.

FIG. 5 shows a third mounting arrangement. In this case, the open end140 of the housing is clamped by diametrically spaced brackets 210 (oneshown in dotted line) that are fastened by suitable means to the innersurface 212 of the ceiling 214. The reaction plate 215 of a clamp 216also engages the inner surface 212 and forms a third point forstabilizing the fixtures 26 on top of the ceiling 214. The ceiling 214has a thin metal sheet 218 which has an edge that extends beyond acenterline 220 in the ceiling 214 to shield the open end 208. The sheet218 has a hole 222 forming a light aperture for the fixture 26.

As shown in FIG. 8, the emergency light portion of fixture 26 isassociated with an emergency lighting circuit 144. The emergencylighting circuit 144 includes a double pole, double throw relay 146 thatselectively connects a battery charger 148 to either charge a gel cell(or cadmium nickel), rechargeable, direct current battery 150 or toconnect the battery 150 to the emergency light bulbs 128, 130.

More particularly, the battery charger 148 has its input terminalsconnected to wires 150, 152 of a 110 volt power supply. The outputterminals are connected to contacts 154, 156 which are electricallyconnected (by means of movable contact carriers 158, 160 when a coil 168is energized) to contacts 162,164 connected to conductors 163, 165,respectively for providing a charging circuit between the anode andcathode terminals of the battery 150. The charging circuit is controlledby relay coil 168 (FIG. 8A) that is connected across the 110 volt powersupply to displace an armature 170 in a direction to close the contacts154, 156. In cases where the 110 volt supply fails, the coil 168 isdeenergized and the armature is returned by a spring 172 in a directionto open the contacts 158, 160 and to close normally open contacts 176,178. The normally open contacts 176, 178, when closed, complete anemergency lighting circuit from the conductors 163,165 throughconductors 180, 182 to opposite sides of the emergency light bulbs 128,130.

A feature of the present invention is that the armature 170 is directlyconnected to a test button 184 which can be pulled to overcome the forceof the coil 168 and directly open the contacts 154, 156 to complete thebattery lighting circuit across the lamps 126, 128, 130 during periodswhen the main power is on and when it is desired to test the emergencylighting.

Combined fixture 26 can be mounted on the ceiling 12 in a location withrespect to an emergency test point represented by reference numeral 199in FIG. 1. The test point is located one foot from the wall of theelevator with the control panel 16 and four feet from the floor 13. Inorder to meet test point candle power requirements, combined lightfixture 26 is located on the ceiling closely adjacent and verticallyabove the test point 199. It has been found that the dedicated bulbs126, 128 and 130 each having lens ends 138 thereon in fixture 26 providesufficient illumination at the test point 200 to meet emergency candlepower requirements in a space 22 when the main power has failed.

The provision of dedicated bulbs for emergency lighting in a common mainlighting fixture housing enables the emergency lighting to be providedin the down lighting system without requiring extra fixture or lenscosts. The dedicated bulbs are used on a standby basis and are not usedfor normal illumination and, therefore, are not subject to burn out.When the main power fails, all emergency lights are connected to thebattery source and are concentrated in one spot directly over the testpoint. They are arranged to illuminate the test point in an unobstructedmanner without requiring that the emergency light bend around baffles orother obstructions heretofore used to partially conceal emergency lightbulb configurations.

Both the illuminating and emergency bulbs can be changed in thecombination light fixture 26 without removing lenses or removing ceilingsegments or use of a ladder.

If desired, a test switch could be placed in series with the relay coiland the test switch could be operated to simulate a power failure to seeif the emergency lighting is standby ready. However, the installation ofthe pull rod on the armature accomplishes the same objective but is lessexpensive than a separate switch.

As described above, emergency lights with three lens end bulbs provide alimited low level illumination for lighting an emergency push button onthe control panel 16. In order to enhance the emergency lightingarrangement in the embodiment of FIG. 9 a light emitting diode (LED) 230is located on the control panel 16 behind an alarm button 232 toilluminate when power failure occurs. To accomplish this purpose, theLED 230 is connected in parallel with three emergency lights 234 thatare selectively connected to an emergency battery 236 by a control relay238 corresponding to relay 146 in FIG. 8. During normal operation the110 volt supply is connected by the control relay 238 to a charger 239for charging the emergency battery 236. Thus, when there is a 110 voltpower supply failure, the LED will illuminate the alarm button 232. Ifdesired, the LED can be of the blinking or flashing type to attract moreattention than a constantly illuminated emergency push button.Alternatively, the LED can be replaced by a passive phosphorescent ring230a shown in dotted line in FIG. 9. The ring 230a is made from a knownphosphorescent material such as halophosphated phosphors, strontiumphosphors and radium. Such materials produce light when exposed tonormal lighting conditions and continue to glow in the dark followingexcitation. In this case, on failure of the 110 volt supply, theelevator is dark. The passive ring 230a will glow to illuminate thealarm button 232.

Another embodiment of the invention is shown in FIG. 10 whichillustrates a typical telephone box 240. The telephone box 240 has anindicator button 242 on its face with a universal symbol of a telephone.The box 240 has a door 244 for covering an access opening 246 to atelephone which is directly wired to a emergency service. In the pastsuch arrangements have exposed the telephone to vandalism or theft. Inaccordance with the present invention the button 242 is illuminated byan LED 248 wired in parallel with the LED of FIG. 9. Such light sourceon the emergency cab telephone cover can be located behind or in anindicator button located on or in the vicinity of the telephone accessdoor 244. In cases where the emergency phone is replaced by a speakerphone the illumination source can be located in the button 244 which isoperable to automatically dial the phone or push it to directly talkwithout dialing.

The embodiment of FIGS. 11 and 12 represent a still further enhancementof the invention shown in FIG. 10. One problem with telephone emergencycalling systems is that the telephone is readily accessible and isthereby subject to theft or vandalism. In accordance with the embodimentof FIGS. 11 and 12, an emergency system is provided which is simpler andless expensive than speaker phone systems which are often used in placeof standard cab phones to prevent access to the telephone. The improvedsystem of this invention enables a standard cab phone to be located inthe elevator behind a selectively opened access door 250. The improvedsystem includes a locking latch 252 which is maintained normally lockedwhen the main power is functioning. Under emergency conditions thesolenoid 254 for the locking latch 252 is energized by the emergencyD.C. power source 256 to release the access door so as to expose a phonehandset 258. As shown in FIG. 11, a plunger 260 of the locking latch 252is spring loaded by a spring 262 to lock against the backside of a sidedoor jamb 264 to prevent the door 250 from being pivoted open about aside hinge 266. In FIG. 12, emergency power is connected by theemergency relay across the wires 268, 269 to energize the solenoid 254to overcome the force of spring 262 so as to retract the plunger 260 toclear the jamb and thereby allow outward swinging movement of the door250 about the hinge 266. Once the door 250 is opened the phone isaccessible for communicating the emergency. As in the previousembodiment a flashing LED 270 can be provided on the door 250 to callattention to the location of the door 250 for opening it once theplunger is retracted as shown in FIG. 12.

An emergency light also can be provided within the phone compartment. Itilluminates when the emergency power source is connected so as to drawan occupant's attention to the phone. If desired the emergency light canbe of the flashing variety to provide still further attention.

In the embodiment of FIGS. 13 and 14 a spring 280 is added between thephone box 282 and a door 284 for swinging the door 284 open when theemergency circuit is operative to energize a solenoid locking latch 286corresponding to latch 252 in FIGS. 11 and 12. When energized, latch 286has its plunger 288 retracted so as to clear the door jamb. In thisembodiment, the elevator cab phone lighting includes three emergencylights 290 on the access door so as to concurrently aid in identifyingand locating the emergency phone while providing a low levelillumination of the elevator under emergency conditions. As in theembodiment of FIG. 8, the three lights 290 are connected to theemergency battery power source when the relay connects the battery powerthereto while disconnecting the charging circuit from the battery whenthe 110 volt power source failure occurs.

FIGS. 15 and 16 illustrated another embodiment of the present inventionwherein a lamp housing 300 and fixture mounting assembly 302 isconfigured to provide for a stable mounting of the lamp housing 300 ontop of a ceiling 304. The lamp housing 300 has an open end 306 with aradially outwardly extending annular flange 308. The annular flange 308defines the entrance to a cavity 310 within the lamp housing 300 formounting a lamp on a socket mounting end 301 of the housing 300. Thelamp can be one or a plurality of lamps as shown in the previouslydescribed embodiment of the invention. The lamp is supported on a socketbracket 303 for illuminating an elevator cab or the like through alighting hole 312 formed through the ceiling 304. The annular flange 308is seated on top of the ceiling 304 in surrounding relationship to thelighting hole 312.

In accordance with the present invention the fixture mounting assembly302 includes three L-shaped retainer members 314 each having an upperleg 316 extending vertically of the outer surface 318 of the lamphousing 300. Each of the L-shaped retainer members 314 also include alower leg 320 that is directed radially outwardly of the lamp housing300 at equidistantly spaced points around the circumference thereof.Each lower leg 320 has a hole 322 therein through which a suitablefastener such as a screw 324 extends to be threadably connected to theceiling 304 at the upper surface thereof. The upper legs 320 are pressedagainst the outer surface 318 by an annular clamp 326 engaged with eachof the upper legs 320 so as to force each of the upper legs 320 intoengagement with the outer surface 318. An adjustment means 328 isconnected to the annular clamp 326 and is operative for tightening andloosening the annular clamp 326 so as to allow it to be verticallyadjusted with respect to the outer surface 318 for accommodatingdifferent thickness ceilings. The adjustment means 328, moreparticularly, includes a U-shaped bracket 330 having a first end 330bconnected to a free end 332 of the annular clamp 326 and having a secondend 330b connected to a fixed end 334 of the annular clamp 326. TheU-shaped bracket 330 carries a nut 334 through which a screw 336 isdirected to press against the free end 332. When the screw 336 istightened it will force the U-shaped bracket outwardly of the lamphousing 300 so as to draw the free end 332 against the lamp housing 300.As shown in FIG. 16, this causes the inside surface of the annular clamp326 to apply a hoop force against annular segments of the outer surface318. When the screw 336 is loosened, the hoop force is releasedpermitting the fixture mounting assembly 302 to be adjusted verticallywith respect to the outer surface 318.

Another aspect of the present invention is that the outer surface 318has a constant diameter annular outer surface 338 that extendsapproximately one half the height of the housing 300 to thereby extendpart way from the open end toward the socket mounting end. The annularouter surface 338 has an upper ledge surface 340 thereon. The housing300 has a plurality of ribs 342 integrally formed therein that extendupwardly from the upper ledge surface 340. Each of the ribs 342 isequidistantly spaced from an adjacent rib and each of the ribs 342 hasan outer surface 344 thereon. If the ceiling is thicker the annularclamp 326 will extend around the outer surfaces 344 of the ribs. Theprovision of the extension ribs 342 enables the housing 300 to be asingle one piece casting using less material while enabling one housingto be adapted for use with the same fixture mounting assembly 302 on awide range of ceiling heights. The outer surfaces 344 of each of theribs 342 are located within a common cylinder having a diameter thatcorresponds to the outer diameter of the annular outer surface 338. Thehousing 300 in addition to being a single unitary casting has ribs 342formed integrally thereof.

The aforedescribed fixture mounting assembly 302 thereby is configuredto define a stable three point platform that will locate the lamphousing 300 on top of the ceiling 304 in a manner that will preventtilting with respect to the lighting hole 312 such that a lamp or lampssupported thereon will remain vertically disposed so that the projectedillumination will be properly directed downwardly into the interior ofthe elevator cab.

Another aspect of the present invention is that the socket plate 303 issecured to the upper surface 300a of the lamp housing 300 at three stakesegments 346 thereof. The socket plate 303 is thereby mounted to definea precision location of connection of a lamp socket within the housing300. Furthermore, the plate 303 is associated with wire leads 348 thatare pressed between the underside of the plate 303 and the upper surface330a such that a connection between the light socket 348 and the wireleads is isolated from strain when the wire leads 348 are connected toother wiring that connects the lamp housing 300 to a suitable powersource.

FIG. 17 illustrates still another embodiment of the invention wherein alamp housing 350 is mounted in a ceiling 352 through a lighting hole 354therein. In this embodiment the lamp housing 350 has a flanged end 356located on the inner surface of the ceiling 352 at an open end 358 ofthe housing 350. The housing 350 has a first annular outer surface 360that extends part way from the open end 358 toward a socket mounting end362. The first annular outer surface 360 includes an upper ledge surface364 thereon. The housing 350 has a plurality of ribs 366 extendingupwardly from said upper ledge surface 364. Each of the ribs 366 has anouter surface 368 located in the same cylinder as the first annularouter surface 360 such that they will define a surface extension toadapt the housing 350 for use in ceilings having the thickness of theceiling 352 in FIG. 17 or having lesser thicknesses. In the case of theillustrated thickness an annular clamp means 370 is engageable with theouter surfaces 368 of the ribs 366 and in the case of a lesser thicknessceiling the clamp means will engage the annular outer surface 360 forsecuring the housing 350 in place within the ceiling. The clamp means370 is like that shown in the embodiment of FIG. 2 including a L-shapedretainer 372 that is fastened by a screw 374 to the ceiling 352 andfurther including an annular clamp 376 that is adjustably secured to theouter surface of the housing 350, either at the ribs 366 as shown inFIG. 17 or at the outer surface 360 if the ceiling is of a lesserthickness. The annular clamp 376 is positioned by an adjustment nut 378and a screw 380 as previously described with respect to the embodimentof FIG. 2. The clamp means 370 thereby is separable from the annularouter surface 360 and engageable with the outer surface 368 of each ofthe ribs 366 for securing the housing on a ceilings of differentthickness.

What is claimed is:
 1. A ceiling mount fixture for an elevator cabcomprising a housing having an open end and a closed end, a flange onsaid open end for fixedly securing said housing to ceilings havingdifferent thicknesses, and a down lighting source within said housinghaving socket means connected to said closed end and a bulb directingdown lighting through said open end;a retainer member extendingvertically from the inner surface of the ceiling in close spacedparallelism with said outer surface of the housing; a retainer clampsurrounding said outer surface of the housing, said retainer clampengaged with said retainer member and including a screw operative toforce said retainer clamp against said retainer member into lockingengagement with said outer surface of the housing while directing a hoopforce on the housing which is radially opposed to the force on saidretainer member.
 2. In the ceiling mount fixture of claim 1, said downlighting bulb including a halogen bulb, a light reflector surroundingsaid halogen bulb to direct light from said halogen bulb verticallydownwardly through said housing and a safety glass cover connected tosaid reflector to diffuse light from said halogen bulb while serving toprevent broken bulb fragments from dropping through said open end.
 3. Inthe ceiling mount fixture of claim 1, said down lighting sourceincluding a fluorescent bulb having a first end directing down lightingthrough said open end and further having a terminal end connected tosaid socket.
 4. A ceiling mount fixture for mounting an illuminatingsource on different thickness ceilings with lighting holes comprising:ahousing including an outer surface, and a closed end; said open endadapted to be mounted with respect to the ceiling in alignment with alighting hole through the ceiling, said ceiling having an inner surface;a retainer member extending vertically from the inner surface of theceiling immediately adjacent the lighting hole and in close spacedparallelism with said outer surface of the housing; a retainer clampsurrounding said outer surface of the housing when aligned with thelighting opening, said retainer clamp engaged with said retainer memberand including a screw operative to force said retainer hoop against saidretainer member into locking engagement with said outer surface of thehousing while directing a hoop force on the housing which is radiallyopposed to the force on said retainer member; a socket in said housing;and a conduit connected to the closed end of said housing to provide forconnection of wires to said socket.
 5. In the ceiling mount fixture ofclaim 4, said closed end including a socket hole for accessing a lightsocket through the closed end into the interior of said housing; asocket mounting plate bridging said opening and a fastener for securingsaid socket mounting plate to said closed end so as to fixedly securesaid light socket thereon.
 6. In the ceiling mount fixture of claim 4,said housing having a height to width ratio in the range of 1 to 1 andsaid retainer member and said retainer clamp being adjustably locatableanywhere along the height of said outer surface of said housingextending above said inner surface of said ceiling.
 7. In the ceilingmount fixture of claim 6, said retainer member being an L bracket with ashort leg and a long leg; said short leg connected to said inner surfaceof the ceiling and said long leg extending vertically from said shortleg closely adjacent the lighting hole through the ceiling; and afastener securing said short leg to said inner surface of the ceiling.8. A ceiling mount fixture for mounting on different thickness ceilingshaving an inner surface and an outer surface and for connection to aflexible conduit type wire system comprising:a housing including anouter surface, a flanged open end and a closed end; a locating flange onsaid flanged open end adapted to overlie the ceiling on said outersurface thereof to cover an access hole through the ceiling and having adiameter in excess of that of said housing to permit insertion of thehousing through the hole and said flanged open end having a retentionsurface engageable with the outer surface of the ceiling when saidhousing is mounted on the ceiling; a retainer member extendingvertically from the inner surface of the ceiling immediately adjacentthe ceiling access hole and in close spaced parallelism with said outersurface of the housing; a retainer clamp surrounding said outer surfaceof the housing when said housing is inserted through the access hole andengaged with the retainer member and including a screw operative toforce the retainer member into locking engagement with said outersurface of the housing while directing a hoop force on the housing whichis radially opposed to the force of the retainer member; a socketlocated inboard of said housing; and a conduit connected to the closedend of said housing including a low profile conduit fitting thatprovides for connection of wires to said socket.
 9. In the ceiling mountfixture of claim 8,said closed end including a socket hole for accessingsaid light socket through the closed end into the interior of saidhousing; a socket mounting plate bridging said opening and a fastenerfor connecting said socket mounting plate to said closed end so as tofixedly secure said light socket thereon.
 10. In the ceiling mountfixture of claim 8, said housing having a height to width ratio in therange of 1 to 1 and said retainer member and retainer clamp beingadjustably locatable anywhere along the height of said outer surface ofsaid housing extending above the inner surface of different thicknessceilings having a height varying between the height of the fixture minusthe thickness of said locating flange and the thickness of said retainerclamp.
 11. In the ceiling mount fixture of claim 10, a plurality of saidretainer members, each of said retainer members being an L-bracket witha short leg connected to the inner surface of the ceiling and a long legextending vertically from said short leg closely adjacent the accesshole through the ceiling; and a single mechanical fastener securing saidshort leg to the inner surface of the ceiling.
 12. In the ceiling mountfixture of claim 4, a primary light connected in said socket, saidprimary light including a halogen bulb, a light reflector surroundingsaid halogen bulb to direct the light from said halogen bulb verticallydownwardly through said housing and a safety glass cover to diffuselight from the halogen bulb while serving to prevent fragments from abroken halogen bulb from dropping through the open end of said housing.13. In a lighting system having a primary lighting means and anemergency lighting means and a test point for measuring the emergencylighting means when primary lighting means has failed the improvementcomprising:a main power supply; the test point located below the ceilingand to one side of a vertical wall disposed below the ceiling; a duallight source located in said ceiling vertically above the test point;said dual light source including a common fixture housing supported onsaid overhead ceiling and having an open end directly exposed to thetest point; said dual light source including a first lamp in said commonfixture housing, said first lamp being a halogen bulb; a reflector forsaid halogen bulb arranged to direct light energy from said halogen bulbinto the space surrounding the test point when a regular power supply isenergized; and said dual light source further including a second lamp insaid common fixture housing including a lens and a battery forenergizing said second lamp only when said main power supply failswhereby said second lamp directs light energy on the test point to anillumination level sufficient to meet minimum emergency lightingstandards.
 14. In a down lighting system for an elevator having aceiling with an outer surface and an access hole therein;a housingincluding an open end and a closed end; a primary source of illuminationincluding a main power supply and a secondary source of illuminationincluding an emergency power supply having a battery; said open endhaving a flange thereon of a diameter in excess of that of said housingto permit insertion of the housing through said access hole and defininga retention surface engageable with the ceiling when the fixture ismounted thereon to interlock the fixture at the outer surface of theceiling; a first socket connected inboard of the housing for connectingsaid first primary source of illumination to said housing; and a secondsocket connected inboard of the housing at a point offset from avertical axis through said first socket for connecting said secondarysource of illumination to said housing and to said battery in saidemergency power supply for directing emergency lighting from the openend of said housing so as to provide an emergency source of illuminationin the space below said ceiling during periods when the primary sourceof illumination is inoperative.
 15. In the ceiling mount fixture ofclaim 14, said primary source of illumination including a primary lightconnected in said first socket, said primary light including a halogenbulb, a light reflector surrounding said halogen bulb to direct thelight from said halogen bulb vertically downwardly through said housingand a safety glass cover to diffuse light from the halogen bulb whileserving to prevent fragments from a broken halogen bulb from droppingthrough the open end of said fixture.
 16. In the ceiling mount fixtureof claim 15, said second socket being located on one side of theinterior surface of said housing, said reflector being located withinsaid housing, and a bulb having a lens thereon; said bulb connected insaid second socket for directing light downwardly between said halogenbulb and said housing for lighting the space below said under emergencylighting conditions.
 17. In the ceiling mount fixture of claim 14, asingle ended fluorescent bulb connected to said first socket, saidsingle ended fluorescent bulb having a reduced lateral width compared tothe width of said housing to provide a wide annular light aperturebetween said single ended fluorescent bulb and the inner surface of saidhousing.
 18. A ceiling mount fixture for mounting a light on differentthickness ceilings having a lighting hole therethrough comprising:ahousing including an outer surface, an open end and a socket carryingend; said open end adapted to be mounted on top of the ceiling inalignment with the lighting hole therein; a first L-shaped retainerhaving an upper leg extending vertically upwardly from the ceilingimmediately adjacent the lighting hole and in close spaced parallelismwith said outer surface of the housing; said first L-shaped retainerhaving a lower leg extending radially outwardly of said open end andadapted to be connected by a fastener to the ceiling; an annular clampsurrounding said outer surface of the housing; said annular clampengaged with said upper leg of said retainer and including an adjustmentscrew operative to force said upper leg into engagement with said outersurface of said housing while directing a hoop force on said outersurface of said housing opposed to the force of said upper leg on saidouter surface of said housing; and said adjustment screw operative forloosening said annular clamp so as to allow said annular clamp to bevertically adjustable with respect to said outer surface foraccommodating different thickness ceilings.
 19. The ceiling mountfixture of claim 18, further comprising second and third L-shapedretainers located equidistantly from each other and from said firstL-shaped retainer and having upper legs thereof held between said outersurface of said housing and said annular clamp and further having lowerlegs extending radially outwardly of said open end and adapted to beconnected by a fastener to the ceiling and said first, second and thirdL-shaped retainers thereby defining a three point support for mountingsaid housing on top of the ceiling.
 20. The ceiling mount fixture ofclaim 19, further comprising said screw located diametrically oppositesaid first L-shaped retainer.
 21. A ceiling mount fixture for mounting alight on different thickness ceiling at lighting holes therethroughcomprising:a housing including an open end and a socket mounting end;said housing having a first annular outer surface extending part wayfrom said open end toward said socket mounting end and including a upperledge surface thereon; said housing having a second annular outersurface of a diameter less than said first annular outer surfaceextending from said upper ledge surface; a plurality of ribs extendingradially outwardly of said second annular surface and upwardly from saidupper ledge surface; each of said ribs having an outer surface thereon;and a retainer clamp surrounding said outer surface of the housing whenaligned with the lighting opening, said retainer clamp engageable witheither said first annular outer surface or said outer surfaces of saidribs: said retainer clamp including a screw operative to force saidretainer clamp into locking engagement with either said first annularouter surface or said outer surfaces of said ribs depending upon thelocation of said retainer clamp vertically on said housing; saidretainer clamp engageable with a portion of said first annular outersurface for securing said housing on a ceiling having a first thickness;said retainer clamp separable from said portion of said first annularouter surface and engageable with said outer surface of each of saidribs for securing said housing on a ceiling having a thickness thatextends the top of the ceiling above said upper ledge surface.
 22. Theceiling mount fixture of claim 21, further comprising said housinghaving a radially outwardly extending flange at said open end thatextends radially outwardly of said first annular outer surface andradially outwardly of said outer surface of each of said ribs.
 23. Theceiling mount fixture of claim 21, further comprising said outersurfaces of each of said ribs being located within a common cylinderhaving a diameter that corresponds to the diameter of said first annularouter surface.
 24. The ceiling mount fixture of claim 22 furthercomprising said outer surfaces of each of said ribs being located withina common cylinder having a diameter that corresponds to the diameter ofsaid first annular outer surface.
 25. The ceiling mount fixture of claim24, further comprising said housing being a single unitary castinghaving said first annular outer surface and said ribs formed integrallythereof.
 26. The lamp housing of claim 21, further comprising a socketmounting plate; a socket on said socket mounting plate having lead wiresconnected thereto; means for staking said socket mounting plate to saidhousing and said lead wires press fit between said socket mounting plateand said housing for eliminating strain at the connection of said leadwires at said socket.
 27. The lamp housing of claim 21, furthercomprising a socket mounting plate; a socket on said socket mountingplate having lead wires connected thereto; means for staking said socketmounting plate to said housing and said lead wires press fit betweensaid socket mounting plate and said housing for eliminating strain atthe connection of said lead wires to said socket.
 28. A ceiling mountfixture for mounting a light on different thickness ceiling at lightingholes therethrough comprising:a housing including an open end and asocket mounting end; said housing having a first annular outer surfaceextending part way from said open end toward said socket mounting endand including a upper ledge surface thereon; said housing having aplurality of ribs extending upwardly from said upper ledge surface; eachof said ribs having an outer surface thereon; and an annular clampengageable with a portion of said first annular outer surface forsecuring said housing on a ceiling having a first thickness; saidannular clamp separable from said portion of said first annular outersurface and engageable with said outer surface of each of said ribs forsecuring said housing on a ceiling having a thickness that extends thetop of the ceiling above said upper ledge surface; said housing having aradially outwardly extending flange at said open end that extendsradially outwardly of said first annular outer surface and radiallyoutwardly of said outer surface of each of said ribs.
 29. A ceilingmount fixture for mounting an illuminating device on different thicknessceilings at light access holes therein and for connection to a flexibleconduit type wire system comprising:a housing including an innersurface, an open end, a closed end and a tubular portion therebetween;said open end having a diameter in excess of said tubular portion topermit insertion of the housing through the access hole and defining aretention surface engageable with the outer surface of the ceiling whenthe fixture is mounted on the ceiling to provide interlocked engagementbetween the ceiling and the housing at the outer surface of the ceiling;light sockets; a wire connected to the closed end of the housingincluding a low profile conduit fitting that provides for connection ofsaid wire to said light sockets; a first primary source of illuminationincluding a primary power supply and a secondary source of illuminationincluding an emergency power supply separate from said primary powersupply; said light sockets including a first socket connected inboard ofsaid housing for connecting said first primary source of illumination tosaid wire for directing primary illumination to a space below saidceiling; and said light sockets including a second socket connectedinboard of said housing at a point offset from a vertical axis throughsaid first socket for connecting said secondary source of illuminationto said emergency power supply for providing emergency lighting from theopen end of said housing so as to provide an emergency source ofillumination in the space below said ceiling because of primary powersupply failure; said primary source of illumination including a primarylight connected in said first socket, said primary light including ahalogen bulb, a light reflector surrounding said halogen bulb to directthe light from said halogen bulb vertically downwardly through saidhousing and a safety glass cover to diffuse light from the halogen bulbwhile serving to prevent fragments from a broken halogen bulb fromdropping through the open end of said housing; said second socket beinglocated on one side of said inner surface of said housing, saidreflector being located concentrically of said inner surface of saidhousing, and a lamp in said second socket having a lens thereon fordirecting light downwardly through the offset space in said housingbetween said halogen bulb and said housing for lighting the space belowthe ceiling light fixture under emergency lighting conditions.